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App Dev Worksheet: Functions

App development lesson 20: Functions · Set 278 · 40 questions
TalentJR

Developer's tip (Write once, use often): function name(parameter) { …; return result; } — call it with name(value). Work out each call separately, then finish the line. Inside a function, if / return can give different results for different inputs.

NameDateTime takenScore ___ / 40
  1. 1.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(5));
  2. 2.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(30, 5));
  3. 3.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(21));
  4. 4.🧰 What does this code show?
    function greet(name) {
      return "Welcome, " + name + "!";
    }
    show(greet("Kabir"));
    (a) Kabir (b) greet (c) Welcome, name! (d) Welcome, Kabir!
  5. 5.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(75, 6));
  6. 6.🧰 What is a function? (a) a type of phone (b) a list of colours (c) a screen size (d) a named block of code
  7. 7.🧰 What does this code show?
    function greet(name) {
      return "Well done, " + name + "!";
    }
    show(greet("Meera"));
    (a) Well done, name! (b) Meera (c) greet (d) Well done, Meera!
  8. 8.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(4));
  9. 9.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(70, 6));
  10. 10.🧰 How do you run (call) a function called greet? (a) #greet (b) greet[] (c) run greet (d) greet()
  11. 11.🧰 What does return do in a function? (a) sends back a value (b) repeats the code (c) closes the screen (d) deletes the app
  12. 12.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(35));
  13. 13.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(3) + points(2));
  14. 14.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(7));
  15. 15.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(6));
  16. 16.🧰 What does this code show?
    function greet(name) {
      return "Well done, " + name + "!";
    }
    show(greet("Aman"));
    (a) Well done, name! (b) Aman (c) Well done, Aman! (d) greet
  17. 17.🧰 In function tip(bill), what is bill? (a) a screen (b) a parameter (c) an event (d) a loop
  18. 18.🧰 What does this code show?
    function greet(name) {
      return "Welcome, " + name + "!";
    }
    show(greet("Meera"));
    (a) Welcome, name! (b) Meera (c) greet (d) Welcome, Meera!
  19. 19.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(22));
  20. 20.🧰 A museum app works out the entry fee. What number does this code show?
    function fee(age) {
      if (age < 5) {
        return 0;
      }
      return 50;
    }
    show(fee(3) + fee(10));
  21. 21.🧰 What does this code show?
    function greet(name) {
      return "Hi, " + name + "!";
    }
    show(greet("Arjun"));
    (a) Arjun (b) Hi, name! (c) greet (d) Hi, Arjun!
  22. 22.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(100, 6));
  23. 23.🧰 A museum app works out the entry fee. What number does this code show?
    function fee(age) {
      if (age < 5) {
        return 0;
      }
      return 60;
    }
    show(fee(5) + fee(6));
  24. 24.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(95, 2));
  25. 25.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(26));
  26. 26.🧰 A museum app works out the entry fee. What number does this code show?
    function fee(age) {
      if (age < 5) {
        return 0;
      }
      return 60;
    }
    show(fee(3) + fee(2));
  27. 27.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(18));
  28. 28.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(3) + points(4));
  29. 29.🧰 What does this code show?
    function greet(name) {
      return "Well done, " + name + "!";
    }
    show(greet("Riya"));
    (a) greet (b) Riya (c) Well done, Riya! (d) Well done, name!
  30. 30.🧰 A museum app works out the entry fee. What number does this code show?
    function fee(age) {
      if (age < 5) {
        return 0;
      }
      return 40;
    }
    show(fee(12) + fee(6));
  31. 31.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(75, 2));
  32. 32.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(11));
  33. 33.🧰 What does this code show?
    function greet(name) {
      return "Welcome, " + name + "!";
    }
    show(greet("Arjun"));
    (a) Arjun (b) greet (c) Welcome, name! (d) Welcome, Arjun!
  34. 34.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(14));
  35. 35.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(5) + points(5));
  36. 36.🧰 What does this code show?
    function greet(name) {
      return "Hello, " + name + "!";
    }
    show(greet("Riya"));
    (a) Riya (b) greet (c) Hello, Riya! (d) Hello, name!
  37. 37.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(39));
  38. 38.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(3) + points(0));
  39. 39.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(25, 2));
  40. 40.🧰 A museum app works out the entry fee. What number does this code show?
    function fee(age) {
      if (age < 5) {
        return 0;
      }
      return 20;
    }
    show(fee(7) + fee(11));

Answer key

  1. 15
  2. 150
  3. 63
  4. Welcome, Kabir!
  5. 450
  6. a named block of code
  7. Well done, Meera!
  8. 8
  9. 420
  10. greet()
  11. sends back a value
  12. 105
  13. 60
  14. 21
  15. 18
  16. Well done, Aman!
  17. a parameter
  18. Welcome, Meera!
  19. 66
  20. 50
  21. Hi, Arjun!
  22. 600
  23. 120
  24. 190
  25. 52
  26. 0
  27. 36
  28. 80
  29. Well done, Riya!
  30. 80
  31. 150
  32. 22
  33. Welcome, Arjun!
  34. 42
  35. 110
  36. Hello, Riya!
  37. 78
  38. 40
  39. 50
  40. 40

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